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The reaction of Fe(OAc)2 and Hbpypz with neutral TCNQ results in the formation of [Fe2(bpypz)2(TCNQ)2](TCNQ)2 (1), in which Hbpypz=3,5‐bis(2‐pyridyl)pyrazole and TCNQ=7,7′,8,8′‐tetracyano‐p‐quinodimethane. Crystal packing of 1 with uncoordinated TCNQ and π–π stacking of bpypz− ligands produces an extended two‐dimensional supramolecular coordination assembly. Temperature dependence of the dc magnetic susceptibility and heat capacity measurements indicate that 1 undergoes an abrupt spin crossover (SCO) with thermal spin transition temperatures of 339 and 337 K for the heating and cooling modes, respectively, resulting in a thermal hysteresis of 2 K. Remarkably, the temperature dependence of dc electrical transport exhibits a transition that coincides with thermal SCO, demonstrating the thermally induced magnetic and electrical bistability of 1, strongly correlating magnetism with electrical conductivity. This outstanding feature leads to thermally induced simultaneous switching of magnetism and electrical conductivity and a magnetoresistance effect. [ABSTRACT FROM AUTHOR]

We report three self‐assembled iron complexes that comprised an anti‐parallel open form (o‐Lanti), a parallel open form (o‐Lsyn), and a closed form (c‐L) of diarylethene conformers. Under kinetic control, FeII2(o‐Lanti)3 was isolated, which exhibited a dinuclear structure with diamagnetic properties. Under light‐irradiation control, FeII2(c‐L)3 was prepared and exhibited paramagnetism and spin‐crossover behaviour. Under thermodynamic control and in the presence of indispensable [FeIII(Tp*)(CN)3]−, FeII2(o‐Lanti)3 and FeII2(c‐L)3 transformed into tetranuclear FeIII2FeII2(o‐Lsyn)2, which exhibited complete spin‐crossover behaviour at T1/2=353 K. [ABSTRACT FROM AUTHOR]

Five lanthanide coordination clusters (CCs) [Ln7(µ3-OH)4(deg)2(Hdeg)2(ben)11]·xCH3CN [Ln = Eu (1), Gd (2), Tb (3), Dy (4), Ho (5); H2deg = diethylene glycol, Hben = benzoic acid; x = 7 for 1–4, x = 6 for 5], with diethylene glycol and benzoic acid as ligands, have been prepared and structurally characterized. All CCs consist of a heptanuclear lanthanide core with a scarce tip-sharing double-butterfly topology. Magnetic measurements revealed that CC 4 exhibits slow magnetic relaxation, with an energy barrier of about 6 K, whereas CC 3 shows outstanding magnetocaloric effects, with an entropy change of 34.6 J Kg–1 K–1 at 2 K and ΔH = 7 T. The photoluminescence properties of CCs 1, 3, and 4 were also investigated, displaying intense characteristic emission spectra of EuIII, TbIII, and DyIII ions. [ABSTRACT FROM AUTHOR]

B Thermally-induced simultaneous switching b of magnetism and electrical conductivity has been realized by a two-dimensional supramolecular coordination assembly composed of Fe SP II sp spin-crossover complexes and partially charged TCNQ (7,7',8,8'-tetracyano- I p i -quinodimethane) radicals. B Thermally-induced simultaneous switching b of magnetism and electrical conductivity has been realized by a two-dimensional supramolecular coordination assembly composed of Fe SP II sp spin-crossover complexes and partially charged TCNQ (7,7',8,8'-tetracyano- I p i -quinodimethane) radicals. Fe SP II sp spin-crossover units are directly linked to -stacked TCNQ columns, thus possessing strongly coupled magnetism (from localized d electrons) and electrical conductivity (from delocalized electrons). [Extracted from the article]